External speed sensor and method

ABSTRACT

An electronic communication wire connecting an input speed sensor and a computer controller in a transmission system is provided. The electronic communication wire connects at one end to the input speed sensor through a first aperture in the transmission case and at the other end to the computer controller through a second aperture in the transmission case. Thus, the electronic communication wire is attached at both ends to internal devices but it partially exists external to the transmission case along the length of the electronic communication wire. The connection between the electronic communication wire and the input speed sensor is sealed with at least a single O-ring while the connection between the electronic communication wire and the computer controller is sealed with at least a pair of O-rings. A method of electronically connecting the input speed sensor and the computer controller externally of the transmission case is also provided.

CROSS REFERENCE TO RELATED APPLICATIONS

This Application claims the benefit of U.S. Provisional Application60/589,245, filed Jul. 20, 2004, which is hereby incorporated byreference in its entirety.

TECHNICAL FIELD

The present invention relates to an electronic communication wire of atransmission case having an externally-mounted feature.

BACKGROUND OF THE INVENTION

In a vehicle transmission system, an electronic communication wiretransmits information collected by an input speed sensor to a computercontroller. In a prior art transmission system, the electroniccommunication wire is routed through an internal area of thetransmission case casting. The prior art internal area of casting isgenerally situated at the exterior of the transmission case opposite apiston pocket. The process of casting the area for internal electroniccommunication includes casting a large mass adjacent to the pistonpocket. This mass increases the likelihood of porosity in thetransmission case in the surrounding area. Manufacturing such aninternal passage then requires angled machining to form the passagethrough the casting. Machining through a porous mass in the seal bore ofthe piston pocket could render the case unusable.

In one transmission system, the computer controller is situated adjacentto an area where sump oil is held. Sump oil may become aerated ifallowed to communicate with rotating parts. Aerated sump oil may createfoam and add accumulation to the transmission. Thus, it is important torestrict sump oil from the transmission's rotating parts.

FIG. 1 illustrates a prior transmission case 10′ design, which has beenimproved by the present invention. The prior transmission case 10′includes an internal communication aperture 100 which provides a passagefor electronic communication wires 102, 104 to connect an input speedsensor and a computer controller. The process of forming the internalcommunication aperture 100 requires angled machining through a castingbehind the piston bore 106 of the transmission case 10′. The castingprocess is followed by angled machining, which could open potentialporosity in the transmission case wall 108 at the piston bore 106.

SUMMARY OF THE INVENTION

The present invention directs the electronic communication wire to thecomputer controller along a path that does not require angled machiningbehind the piston bore and, thus, avoids the potential of a poroustransmission case. Further, the electronic communication wire isdirected to a computer controller along a path external to thetransmission case. The present invention also prevents sump oil fromgaining access to the moving parts located in the transmission casewhile providing electronic communication between an input speed sensorand a computer controller.

In summary, the transmission case design of the present inventionprovides for electronic communication between an input speed sensor anda computer controller of a transmission system. The transmission casehas a first aperture to allow access to the input speed sensor and asecond aperture to allow access to the computer controller. A portion ofan electronic communication wire, enclosed in a flexible sheath, existsexternal to the transmission case and connects to the input speed sensorvia the first aperture and to the computer controller via the secondaperture. The wire connects to the second aperture adjacent to an areawhere sump oil is held. Thus, the connection at the second aperture issealed with two O-ring seals to prevent sump oil from exiting the sumparea of the transmission case via the second aperture. The connection atthe first aperture, however, is only subject to incidental oil contactand, thus, only requires a single O-ring seal. At least one rib extendsfrom the transmission case adjacent to the input speed sensor andelectronic communication wire. The rib projects further from thetransmission case than the input speed sensor and electroniccommunication wire to protect the input speed sensor and electroniccommunication wire from damage, particularly during transit andassembly.

Further, a transmission case for a transmission system is provided. Thetransmission case houses a computer controller, an input speed sensor,and an electric communication wire. The electric communication wireconnects the input speed sensor and the computer controller. Thetransmission case has the electric communication wire located externalto the transmission case, a first aperture in the transmission caseadapted for access to the input speed sensor, and a second aperture inthe transmission case providing access to the computer controller. Thetransmission case also comprises an external connector including theelectric communication wire having an input speed sensor plug, which isengageable with the first aperture, and a computer controller plug,which is engageable with the second aperture. Further, at least one ribis located on the transmission case sufficiently adjacent to the firstaperture to partially enclose at least one of the input speed sensorplug and the electronic communication wire.

Another aspect of the invention provides an electronic communicationwire connector. The electronic communication wire connector is adaptedfor use with a transmission case housing a computer controller and aninput speed sensor. The transmission case has a first access to theinput speed sensor and a second access to the computer controller. Theelectronic communication wire connector is locatable external to thetransmission case to provide electronic communication between the inputspeed sensor via the first access and the computer controller via thesecond access.

The present invention also provides a method of connecting a computercontroller and an input speed sensor housed in a transmission case. Themethod includes forming a first aperture in the transmission caseproviding access to the input speed sensor, forming a second aperture inthe transmission case providing access to the computer controller, andconnecting the input speed sensor with the computer controllerexternally of the transmission case and between the first aperture andthe second aperture.

The above features and advantages and other features and advantages ofthe present invention are readily apparent from the following detaileddescription of the best modes for carrying out the invention when takenin connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a fragmentary schematic cross-section of a prior transmissioncase design improved by the present invention;

FIG. 2 is a fragmentary schematic cross-sectional view of thetransmission case in accordance with the present invention;

FIG. 3 is a fragmentary perspective view of the transmission case inaccordance with the present invention with an external electroniccommunication wire removed;

FIG. 4 is a fragmentary perspective view of the transmission case inaccordance with the present invention with the external electroniccommunication wire of this invention installed; and

FIG. 5 is a schematic side view of a second embodiment of the presentinvention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 2 illustrates an embodiment of a portion of a transmission case 10in accordance with the present invention. The case has a first aperture12 aligned to provide access for an input speed sensor plug 14. The casehas a second aperture 16 aligned to provide access for a computercontroller plug 18. An electronic communication wire 20 connects theinput speed sensor plug 14 to the computer controller plug 18 to providean external connector 22 for electronic communication between a speedsensor and a computer controller within the transmission case 10. Theelectronic communication wire 20 connects to the input speed sensor plug14 which is adapted to plug into the first aperture 12, and sealed witha single O-ring 26 to prevent incidental oil from exiting a sump area 38of the transmission case 10 at the first aperture 12, particularly whenthe vehicle is in motion. The electronic communication wire 20 iscomprised of a pair of wires 30 which run through a sleeve flexiblecovering 32 between the input speed sensor plug 14 and the computercontroller plug 18 to connect the input speed sensor at the firstaperture 12 to the computer controller at the second aperture 16. Thesleeve 32 may be a flexible coating adhered to the electroniccommunication wire 20. The sleeve 32 may also be a flexible tube intowhich the electronic communication wire 20 is removably inserted. Thesecond aperture 16 may be sealed with a pair of O-rings 34, 36. A pairof O-rings 34, 36 is appropriate at the second aperture 16 because sumpoil is stored in the sump area 38 adjacent to the second aperture 16.The pair of O-rings 34, 36 prevents sump oil from leaking around thesecond aperture 16 and dripping out of the transmission case externally.

The piston pocket 40 of the transmission case 10 is also illustrated inFIG. 2. The piston pocket 40 is generally cast into the transmissioncase 10. A bore seal (not shown) is utilized in the piston pocket 40. Ifthe piston pocket 40 is porous along its inner surface, the bore sealtherealong cannot form a tight seal between the piston pocket 40 and,thus, the surface of the piston and the transmission case 10 isunusable. The present invention does not require a large castingadjacent to the piston pocket 40 and, therefore, reduces the risk ofporosity in the piston pocket 40.

FIG. 3 illustrates an exterior view of a portion the transmission case10 in accordance with the present invention. The first aperture 12 andsecond aperture 16 of the transmission case 10 form the input speedsensor plug receptacle and the computer controller plug receptacle,respectively. Ribs 50, 52 are formed in the transmission case 10adjacent to a path between the first aperture 12 and the second aperture16. Referring to FIGS. 2 and 3, ribs 50, 52 provide protection for thetop of the input speed sensor plug 14 and the encased pair of wires 30when the connector 22 is attached to the transmission case 10, asdefined in FIG. 2. The ribs 50, 52 extend further from the surface ofthe transmission case 10 than the top of the input speed sensor plug 14and the connector 22 to protect them from damage, particularly duringtransit and assembly.

FIG. 4 illustrates a portion of the transmission case 10 with theexternal connector 22 plugged into the first and second apertures 12, 16or plug receptacles. The transmission case 10 has the first aperture 12and the second aperture 16 formed to receive the input speed sensor plug14 and computer controller plug 18, respectively. The pair of wires 30provides electronic communication between the input speed sensor and thecomputer controller.

FIG. 5 illustrates a second embodiment of the present invention 22′. Theinput speed sensor plug 14′ and the computer controller plug 18′ areconnected by the electronic communication wire 20′. The electroniccommunication wire 20′ consists of a pair of wires 30′ encased in asleeve 32′. The input speed sensor plug 14′ includes a single O-ring 26′and the computer controller plug 18′ includes a pair of O-rings 34′,36′.

As illustrated in FIG. 2, the invention also provides an electroniccommunication wire connector 22 adapted for use with a transmission case10. The electronic communication wire connector 22 has a first end 13including an input speed sensor plug 14 and a second end 17 includingcomputer controller plug 18. The input speed sensor plug 14 is adaptedto plug into a first access 15 to the input speed sensor and thecomputer controller plug 18 is adapted to plug into a second access 19to the computer controller. An external electronic communication wire 20exists between the plugs 14, 18 to define a path adapted for electroniccommunication external to the transmission case 10. Although the firstaccess 15 and second access 19 are illustrated in FIG. 2 as aperturesthat the input speed sensor plug 14 and computer controller plug 18 pluginto they may be of any design that provides for electroniccommunication between the computer controller and the input speedsensor.

The present invention also provides a method of connecting a computercontroller and an input speed sensor housed in a transmission case 10,as viewed in FIGS. 2, 3, and 4. The method comprises forming a firstaperture 12 in the transmission case 10 providing access to the inputspeed sensor and forming a second aperture 16 in the transmission case10 providing access to the computer controller. The method alsocomprises connecting the input speed sensor with the computer controllerexternally of the transmission case 10 and between the first aperture 12and the second aperture 16.

While the best modes for carrying out the invention have been describedin detail, those familiar with the art to which this invention relateswill recognize various alternative designs and embodiments forpracticing the invention within the scope of the appended claims.

1. A transmission case assembly having a transmission case housing acomputer controller, an input speed sensor, and an electroniccommunication wire connecting the input speed sensor and the computercontroller, said transmission case assembly comprising: the electroniccommunication wire being located external to the transmission case; afirst aperture formed in said transmission case providing access to theinput speed sensor; a second aperture formed in said transmission caseproviding access to the computer controller; an external connectorincluding said electronic communication wire having an input speedsensor plug configured to be engaged with said first aperture and acomputer controller plug configured to be engaged with said secondaperture; and at least one upstanding rib on said transmission casesufficiently adjacent to said first aperture to partially protect atleast one of said input speed sensor plug and said electroniccommunication wire from damage.
 2. The transmission case assembly ofclaim 1, wherein the electronic communication wire is covered with aflexible sleeve.
 3. The transmission case assembly of claim 1, whereinthe at least one rib protects the input speed sensor from damage.
 4. Thetransmission case assembly of claim 1, wherein the at least one ribprotects the electronic communication wire from damage.
 5. Thetransmission case assembly of claim 1, including a first seal betweenthe first aperture and the input speed sensor plug and a second sealbetween the second aperture and the computer controller plug.
 6. Thetransmission case assembly of claim 1, wherein a seal between theelectronic communication wire and the computer controller plug iscomprised of two or more O-ring seals.
 7. The transmission case assemblyof claim 1, wherein said input speed sensor has an access and said inputspeed sensor plug is configured to be engaged with said access toprovide electronic communication to said input speed sensor.
 8. Thetransmission case assembly of claim 1, wherein said computer controllerhas an access and said computer controller plug is configured to beengaged with said access to provide electronic communication to saidcomputer controller.
 9. The transmission case assembly of claim 1,wherein said at least one upstanding rib on said transmission case isadjacent to a path between said first aperture and said second aperture.